This invention is directed generally to roadway barriers, and more particularly, to roadway barriers used during roadway construction for protection of roadway construction workers, construction equipment in work zones, and the traveling public.
Work zones on roadways are dangerous environments for construction personnel and vehicle operators. Traditionally, temporary barriers have been placed between vehicular travel lanes and work zones to prevent vehicles from entering the work zones. Barriers have been formed in numerous configurations and have had various degrees of success. For example, barriers have been formed from multiple concrete segments having heights between about three feet and about six feet and have been formed from continuous asphalt having a height of about eight inches.
Historically, the design of longitudinal barrier systems has focused primarily on issues such as redirection capability, minimization of vehicle intrusion into a work zone, and portability. Barrier systems must be capable of redirecting a variety of different types of vehicles in a smooth and stable manner without causing vehicle rollover. The barriers must also limit vehicle intrusion into the work zone. Barriers having high profiles with substantial mass achieve these design criteria. However, the temporary nature of most work zones also requires that the barrier systems be lightweight and portable so that the barriers can be installed, repositioned, and removed with minimal effort.
Barriers meeting most of these criteria are high profile concrete barriers having short segment lengths. The short segment lengths produce barriers that are relatively lightweight and portable, yet are strong enough to absorb the forces generated by a vehicle colliding with the segment and redirect the vehicle. Unfortunately, high profile barriers are not optimal and create additional hazards. For example, longitudinal concrete barriers possessing a relatively high height, such as between about three to about six feet, provide excellent separation of roadway traffic from roadside work zones. An errant vehicle coming into contact with these barriers is safely redirected back onto the roadway, thus protecting both the driver and construction personnel present in the work zone. However, while high profile barriers provide excellent redirection and separation capabilities, the high profile barriers can also obscure a driver""s field of view of cross traffic and lead to accidents.
On the other hand, low-profile barriers having heights up to about one foot provide increased visibility but do not safely redirect vehicles away from the work zone on a consistent basis. Instead, the low-profile barriers fail to prevent vehicles from entering work zones, which in turn endangers the lives of the construction personnel working in the work zones.
Thus, a need exists for an alternative design for conventional high and low profile barriers.
This invention is a low-profile portable roadway barrier for preventing vehicles from entering work zones on roadways by redirecting the vehicles onto roadways. The roadway barrier gives a vehicle operator a greater field of vision than the field of vision available to vehicle drivers when conventional high-profile roadway barriers are used. The roadway barrier system, consisting of multiple individual roadway barriers may be configured to be easily movable to define the ever changing perimeter of a roadway work zone.
The roadway barrier may be formed from an elongated body having an impact surface for absorbing forces caused by at least one vehicle contacting the elongated body, a bottom surface for contacting a ground surface, a first end, and a second end. The roadway barrier may have an overall height between about one foot and about three feet. The roadway barrier may also include a leg coupled to the elongated body and positioned generally parallel to the elongated body for providing additional support during a collision between a vehicle and the barrier. The roadway barrier may be supported by support brackets for coupling the roadway barrier to adjacent roadway barriers. The roadway barrier transfers forces received by the elongated body to adjacent barriers using the support bracket.
The roadway barrier is configured to absorb forces generated by a vehicle colliding with the roadway barrier without significant movement of the barrier. The roadway barrier absorbs these forces by absorbing a portion of the force and transferring the remainder of the force to adjacent barriers through structures coupled to the ends of the roadway barriers. In one embodiment, roadway barriers transfer forces generally orthogonal to the impact surface to adjacent roadway barriers using one or more keys and keyways. The key may be a threaded shear pin in one embodiment, and the keyway may be a slot. The forces received by the elongated body that are generally parallel to the elongated body may be transferred to adjacent roadway barriers using a support bracket. By transferring forces imparted by a vehicle on the roadway barrier to adjacent barriers, the amount of force a roadway barrier is capable of absorbing is increased without increasing the weight of the roadway barrier. Support brackets coupled to adjacent roadway barriers may be coupled to each other using a support member, such as, but not limited to, a rod. Support brackets are configured with a high tolerance for misalignment between roadway barriers, thereby enabling the roadway barriers to be easily coupled together. In one embodiment, a support bracket may be coupled to the elongated body and to the leg of a roadway barrier.